Field
Several embodiments of the present invention are directed to novel compositions comprising multipotent cells and/or microvascular tissue, which has been sterilized and/or treated to inactivate any viruses, and methods for their preparation and allogeneic or xenogeneic use in treating or preventing tissue injury and diseases, such as, e.g., arthritis.
Description of the Related Art
Injuries to soft tissues, such as muscles, tendons, ligaments, and joint capsules, occur quite frequently. Such injuries typically result in tissue dysfunction characterized by pain, inflammation and internal tissue stress, and can ultimately result in a functional disability. For example, while sprains to tendons will heal spontaneously, complete tears of a tendon will often lead to disability if not surgically treated. Even despite surgical repair, about 15% of Achilles tendon and 40% of two tendon rotator cuff repairs subsequently fail. Furthermore, the repaired tendon seldom returns to pre-injury strength and function levels.
Tissue repair generally includes several phases, including an initial inflammatory response followed by cellular proliferation and tissue remodeling. Fundamental processes of tissue repair include both fibroplasia and angiogenesis. Fibroblasts activated by inflammatory mediators migrate into the wound, proliferate, and lay down collagen-rich extracellular matrix, while capillaries in the damaged tissue grow towards the repair zone to reestablish blood flow. During the remodeling process, scar tissue is reabsorbed and replaced with denser, oriented collagen, to produce tissue with some of the characteristics of the original tissue.